Explosively actuated press



NOV. 6, 1962 TEMPLE ETAL 3,062,260

EXPLQSIVELY ACTUATED PRESS Filed July 18, 1960 2 Sheets-Sheet l INVENTORS ROBERT TEMPLE w/wssr 5. raw/=4 5.

2; rarA/s 71s 1962 R. TEMPLE ETAL 3,

EXPLOSIVELY ACTUATED PRESS Filed July 18. 1960 2 Sheets-Sheet 2 Z( O 0 H INVENTORS.

ROBERT TEMPLE,

3,062,260 EXPLOSIVELY ACTUATED PRESS Robert Temple, Swissvale, Ernest E. Temple, Murraysville, and Joseph L. Giebel, Swissvale, Pa, assignors to Mine Safety Appliances Company, a corporation of Pennsylvania Filed July 18, 1960, Ser. No. 43,506 3 Claims. (Cl. 153-1) This invention relates to explosively actuated presses for compressing metal sleeves and the like around wires and rods.

A press of the general character disclosed herein is shown in Patent 2,149,641, particularly FIG. 9 thereof. The end of a wire is secured in the sleeve of an electrical connector by tightly compressing the sleeve around the wire. The sleeve compression is effected by two dies that are forced together by pistons that are driven toward each other by expanding gases when an explosive cartridge is detonated. The dies are held in engagement with the pistons and, before the press is used, the dies are spaced a considerable distance apart so that the pistons can acquire high velocity before pressure is applied to the sleeve. Consequently, provision has to be made for holding the sleeve centered between the die recesses until it is struck by the dies. That is done by means of a notched jig, which cannot be used if a sleeve is compressed around the ends of two wires that cannot be removed endwise from the press after splicing.

It is among the objects of this invention to provide a press similar to the one shown in the abovennentioned patent, but in which the dies themselves will hold the sleeve or other work in place until the explosive actuating charge is fired, and from which spliced wires can be removed.

In accordance with this invention an elongated housing is provided with a pair of axially aligned bores closed at their outer ends to form cylinders. Disposed in each cylinder is a piston that normally is located at the outer end of the cylinder. The inner ends of the cylinders are spaced apart by a central portion of the housing which is provided with a transverse passage through it. The inner ends of the cylinders open into the opposite sides of the passage. A pair of laterally spaced dies are slidably disposed in the passage in positions where they will be struck by the pistons and driven toward each other. The two dies have opposed work-receiving recesses, and the opposite sides of the passage have dieengaging shoulders that hold the dies close enough together for them to hold work in their recesses unassisted by other elements. The housing also has an explosion chamber and passages that connect it with the outer ends of both cylinders. Means is provided for discharging an explosive cartridge in the chamber to drive the pistons toward each other for compressing work in the die recesses.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in which FIG. 1 is a side view of our press;

FIG. 2 is an end view thereof;

FIG. 3 is an enlarged side view, but with most of the press shown in longitudinal section;

FIG. 4 is a fragmentary horizontal section taken on the line IVIV of FIG. 3; and

FIG. 5 is an enlarged fragmentary longitudinal section showing work compressed by the dies.

Referring to the first four figures of the drawings, a long metal block 1 is provided with a pair of axially aligned longitudinal bores 2 that extend inwardly toward each other from the opposite ends of the block. The outer end of each bore is threaded and receives a screw 3,952,2h9 Patented Nov. 6, 1962 r ce plug 3 to tightly close it, whereby each bore forms a cylinder. The inner ends of the two cylinders are spaced apart by a central portion 4 of the block, which is provided with a transverse passage 5 extending entirely through it. The inner ends of the cylinders open into the opposite sides of this passage by means of wide slots 6 that have parallel upper and lower walls extending the full width of the block. The structure described this far forms the housing of the press.

A piston 8 is slidably mounted in each cylinder and is normally held at the outer end thereof by means of a spring-pressed detent 9 slidably mounted in the cylinder wall beside the outer end of the piston. The outer ends of the cylinders are connected by passages 10 and 11 with a combustion or explosion chamber 12 at the inner end of a plug 13 screwed into a central threaded opening in the top of the block. The chamber is at the inner end of a cartridge 14 removably mounted in the plug. A breechblock 16 is screwed on to the outer end of the plug to hold the cartridge in the plug and to support a firing pin 17, which normally is maintained in a retracted position by means of a coil spring 18. The cartridge can be fired by striking the outer end of the pin with a hammer or the like, and then the expanding gases will drive the two pistons toward each other. They can be pulled apart and returned to their outer positions in the cylinders by first removing screw plugs 3 and then screwing pull rods (not shown) into threaded holes 19 in the outer ends of the pistons.

When the pistons are driven toward each other they strike a pair of dies 21 that are located between them in transverse passage 5 of the housing. The dies extend entirely through the housing so that their ends are flush with the housing side walls. The adjacent or opposed faces of the dies are each provided with a semicircular recess 22 which, when the dies are together, will form a circular opening having the same diameter that the work that is to be compressed is to have after compression. Normally the dies are just far enough apart to permit them to receive and hold the uncompressed work, such as a metal sleeve 23 encircling one or more wires 24. Thus, the sleeve, having a greater radius than the recesses, will be engaged by their edges and will project part way into the recesses. The dies are held in this work-holding position by means of die-engaging shoulders 25, with which the opposite sides of the transverse passage 5 are provided. In other words, these shoulders limit the distance that the dies can be separated. They also insure a predetermined space between each die and its driving piston, so that the piston can develop the necessary velocity before striking the die. When the dies are driven together by the pistons the sleeve will be compressed in the die recesses to a smaller diameter, as shown in FIG. 5.

It is preferred that each die extend through the slot 6 in the adjoining side wall of passage 5 and also into the inner end portion of the adjoining cylinder 2. In order to do this, the housing at opposite sides of each cylinder must be provided with openings 27 for receiving the ends of a die. These openings extend back behind the dies to allow escape of air from the cylinders as the pistons are driven forward. Preferably, the outer or back sides of the dies are convex in vertical section, and the adjacent ends of the pistons are provided with concave recesses 28 that fit the dies when they are driven together. The pistons are prevented from rotating by means of guide pins 29, which contain detents 9 and project from the bottom of the cylinders up into longitudinal grooves 30 in the pistons.

With the dies arranged as disclosed herein, they usually must be applied to sleeve 23 before they are inserted in the housing. The assembly then is inserted endwise in housing passage 5 and centered therein. The dies are held in correct position by spring-pressed detents 32 slidably mounted in the housing and projecting up into transverse grooves 33 in the bottoms of the dies. After a sleeve has been compressed around a pair of wires, it may be necessary to remove the dies from the housing before the sleeve can be removed from between them. Even then, it wili be necessary to remove the spliced wire from the housing. That is done by pulling the wire down through a slot 34 that connects the bottom of the housing with passage 5. The slot is at least as wide as the space between the dies when they are against shoulders 25.

With this press the work is held in operating position by the compression dies themselves, and the pistons nor mally are spaced from the dies. Advantages are that the dies can be removed readily and reinserted in the housing to facilitate their separation from the work, and that separate means for holding the work are unnecessary.

According to the provisions of the patent statutes, we have explained the principle of our invention and have illustrated and described what we now consider to represent its best embodiment. However, we desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

We claim:

1. A press comprising an elongated housing provided with a pair of axially aligned bores closed at their outer ends to form cylinders, a piston slidably disposed in each cylinder and normally located at its outer end, the inner ends of the cylinders being spaced apart by a central portion of the housing provided with a transverse passage therethrough, the inner ends of the cylinders opening into the opposite sides of the passage, a pair of laterally spaced dies slidably disposed in said passage in positions to be struck by the pistons and driven toward each other, the dies having opposed work-receiving recesses, said opposite sides of the passage having die-engaging shoulders holding the dies spaced from the pistons normally and 4 close enough together for them to hold work in said recesses, the housing having an explosion chamber and passages connecting it with the outer ends of both cylinders, and means for discharging an explosive cartridge in said chamber to drive the pistons toward the dies for compressing Work in said die recesses.

2. A press comprising an elongated housing provided with a pair of axially aligned bores closed at their outer ends to form .cylinders,.a piston slidably disposed in each cylinder and normally located at its outer end, the inner ends of the cylinders being spaced apart by a central portion of the housing provided with a transverse passage therethrough, the inner ends of the cylinders opening into the opposite sides of the passage, a pair of laterally spaced dies slidably disposed in said passage, means connected with said housing removably retaining the dies in said transverse passage, the adjacent ends of the pistons and dies normally being spaced apart and the dies having opposed work-receiving recesses, said opposite sides of the passage having die-engaging shoulders holding the dies close enough together for them to hold work in said recesses, the spaces between the pistons and dies being completely free of obstructions, the housing having an explosion chamber and passages connecting it with the outer ends of both cylinders, and means for discharging an explosive cartridge in said chamber to drive the pistons toward the dies for compressing work in said die recesses. i

3. A press according to claim 2, in which said dieretaining means are spring-pressed detents normally projecting from a wall of said transverse passage into grooves in the dies extending lengthwise of the pistons.

References Cited in the file of this patent UNITED STATES PATENTS 2,030,803 Temple Feb. 11, 1936 2,149,641 Temple Mar. 7, 1939 FOREIGN PATENTS 815,541 Great Britain lune 24, 1959 

